This invention relates generally to the attainment of better air-fuel mixture ratios in air-fuel streams delivered to internal combustion engine cylinders; more particularly, it concerns the unusually advantageous use of an air metering valve in the crankcase gas recycling path and in the fuel supply path associated with an engine.
It is found that conventional engines normally burn or combust only 50 to 60 per cent of their gasoline supply, due primarily to inadequate metering of air or oxygen to the gasoline feed. As a result, when the mixture is brought up to flash point, there if often insufficient oxygen present to combine with the fuel molecules, so that not all the fuel can burn and release its energy. This deficiency is aggravated by recycling of crankcase gases to the air-fuel stream, as is currently advocated to reduce smog. Also, it is found that the fuel is often incompletely vaporized, which lowers engine efficiency.